Elevator door lock



Oct. 11, 1949. J. H. BORDEN 2,484,679

ELEVATOR DOOR LOCK Filed June 5, 1946 C5 Sheets-Sheet l I is. 1..

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' 1N VEN TOR. Joseph H. Border? NTTOlP/VEYS Oct. 11, 1949. J. H. BORDEN ELEVATOR DOOR LOCK Filed June 5, 1946 3 Sheets- Sheet 2 INVENTOR. uasep/r H. 50rd? BY 0/14 1 4 6' ATTORNEYS Oct. 11, 1949.

J. H. BORDEN ELEVATOR DOOR LOCK 3 Sheets-Sheet 3 Filed June 5, 1945 INVENTOR. dosepfi H 517/01 0 Patented Oct. 11, 1 949 ELEVATOR DOGR LOCK 1 Joseph H. Borden, Toledo, Ohio, assignor to The Haughton Elevator Com corporation of Ohio pany, Toledo, Ohio, a

Application June 5, 1946, Serial No. 674,564

1 Claim. (01. 137-31) This invention relates to a lock for counterbalanced elevator doors. I

An object of the invention is to-provide a lock that locks together the upper and lower halves of a counterbalanced door.

A further object of the invention is to provide a lock that will lock the counterbalanced elevator door regardless of the change in elevation of the door when closed, due to wear on' the chain connecting the door halves;

A further object of the invention is to provide a lock for counterbalanced elevator doors that can be unlocked only when the elevator car is in position at that floor, and that will function satisfactorily throughout a considerable range of vertical position of the meeting point of the two halves of the door.

Other objects and details of the invention will appear :as the description proceeds.

In the drawings forming :a part of this specification, Fig. 1 is a horizontal section of a corner of an elevator shaft showing a lock embodying one form of the invention and co-operative parts.

Fig. 2 is a vertical section on the line 2-2 of Fig. 1.

Fig. 3 is a view similar to Fig. 2, but showing the parts as the door begins to open.

Fig. 4 is a detail section on the line 44 of Figs. 2 and 3.

In the construction shown in the drawings, the lock is shown applied to a door consisting of an upper half IO and a lower half II, counterbalanced by a chain connected to the two halves and passing over a pulley, so that as the bottom half goes down the top half goes up, and the two halves counterbalance each other. This is a wellknown arrangement, and is not shown.

The lower half II has a bracket I2 thereon to which is pivoted, at I3, a catch I4. Extending below the pivot there is a heel I5 on the catch which is pressed outward by a spring I 6 but permitted to move inward an adjustable distance determined by a set screw H. The catch includes a hook l8 which engages a projection IS on upper half I I] when the door is looked, as shown in Fig. 2.

Catch I4 is also provided with an arm 20 which is provided with an adjustable stop screw 2| which limits the distance to which hook I8 can move over projection I9. Arm 20 then turns and runs roughly parallel with hook I8, and is provided with a cam surface 22. Also on one side of arm 20 there is an insulating block 23 carrying a plate 23' which bridges two spring contacts 24 mounted in a casing 25 fixed to the wall of the elevator shaft. Wires 26 lead from contacts 24 to a switch in a safety circuit which prevents operation of the elevator when bridge 23' is not in place. V I

Also mounted in casing 25 there is a rock shaft 27 having an arm 28 carryin roller 29. Another arm- 30 on the rock shaft is pressed outward by a spring 3| and normally holds roller 29 against the casing well. Another arm 32' on the rock shaft 21 carries a roller 33 in position to be contacted by a cam 34, shown in Fig. 2 in its retired position.

Cam 34 is operated by well known means so that it is normally in its Fig. 2 position, and can be projected, as shown in Fig. 3, only when the elevator car is in position at that floor.

The operation of the device has been indicated in connection with the description of its structure, but for convenience the operation may be briefly summarized.

Assuming that the door is locked, as shown in Figs. 1 and 2, the car is brought to position at that landing, and then cam 34 can be operated to contact roller 33 and swing it to the position in which it is shown in Fig. 3. By this movement, shaft 21 is rocked, and roller 29, contacting surface 22, moves hook I8 out of engagement with projection I9, thereby unlocking the door so that its halves may be separated.

The rocking of catch 14 which releases hook I8 also moves arm 2|] so that the bridge plate '23 carried thereby moves away from contacts 24,

opening the safety circuit and making certain that the car will stay at that landing until the door is again closed.

After the door has been closed, cam 34 is retired, permitting spring I6 and gravity to move hook I8 into locking position, at the same time returning plate 23' to its bridging position against contacts 24, thereby closing the safety circuit and allowing the car to be moved away from that landing. The door cannot be unlocked until the car returns to the landing so that cam 34 can be again advanced.

It will be noted that the vertical elongation of surface 22 and bridge plate 23' is sufiicient so that a very considerable change in the vertical position of the door when closed does not alter the operation of the lock. This allows for any variation in length of the chain uniting the door halves or other variation due to normal wear or other normally encountered conditions. Therefore, the lock not only operates initially to lock the door halves together except when the car is at that landing and insure that the car will not move away from the landing with the door unlocked, but it continues to perform these functions reliably regardless of wear and normal variations in the position of the closed door. The shape of the lock actuating means or catch I4 on the door and the operating means, or roller 29, mounted in the car shaft, may be widely changed, and therol-ler might be'on-the catch and the'elongated contact surface on arm "28 with similar results, the essential feature being that there is on one of the parts a vertical surface which serves for operative contact,:;so that the operation is unaffected by variation in relative vertical position.

Not only does the lock operate correctly through as great variations in the vertical position of the doors as required, but looking 'thee-twodoor halves together insures that neither half can be moved by itself. Certain prior devices have locked only the lower half, allowing the upper half tobe lifted regardless of the door--lock,--and this has made accidents possible.

*While one simplean'd-practical embodiment of the invention has been disclosed in considerable-"detail, itwill be understood that variations in the construction may be made within the scope of the appended claim while retaining some advantages of the invention.

A lock for an elevator door consisting of upper and lower counterbalanced parts, said lock comprising a latch on one of said parts, a projection on the other part with which the latch may have locking engagement When the door is entirely closed, the projection having a vertical face of material extent engaging the latch as the door portions approach-closed position "and maintaining 'theIatch out of locking position until the door is completely closed, and an interlocking safety switch having one contact in rigidly fixed relationito the latch and the other contact in fixed position in the elevator shaft, one of said itwo contacts 'havinga vertically elongated contactsurface, whereby identical switch operation occursthroughout' an appreciable vertical variatiorrnfaithe. meetingpoint of the door portions.

JOSEPH H. BORDEN.

REFERENCES orrnn The following references are of record in the file of this .patent:

UNITED STATES PA'IENTS Number Name Date 1328;309 'We-xler Jan. 20, 1920 1,864,959 Talen June 28,1932 1,898,450 ,I-Iutton,. Feb. 21, 1933 2,240,820 Wilm'ot May 6, 1941 

